When the Egyptian authorities released a video last week describing plans to resurface the Pyramid of Menkaure, the smallest of Giza’s three main pyramids, with the granite blocks that once clad part of its exterior, the initial reaction was swift — and harsh.

Some archaeologists criticized the idea. An online comment that was widely picked up by news organizations likened it to trying to “straighten the Tower of Pisa.” Others worried that covering the familiar limestone walls of the pyramid with new cladding would have the effect of turning the historic Giza plateau into an ersatz Disneyland.

The initiative was announced by Mostafa Waziri, the secretary general of Egypt’s Supreme Council of Antiquities, who called it “the project of the century” in a video posted Jan. 25 on social media. He has said the endeavor, led by a coalition of Egyptian and Japanese experts, would begin with at least a year of study, and that an international team would then decide whether to proceed with trying to restore the granite blocks that once covered roughly the bottom third of the pyramid.

Dr. Waziri did not return emails or a phone calls seeking comment. In an interview with the satellite TV station Ten on Tuesday evening, he dismissed criticism that has erupted online as “social media talk that has no basis in truth.”

Some online critics seemed to be under the impression that the smooth granite blocks visible in videos and photos of the pyramid — which contrast sharply with the more familiar textured limestone above — were new. But several Egyptologists said that they appeared to be the pyramid’s surviving granite blocks, which have been there for centuries, and which can be seen in photographs dating back to 1907.

The debate over the pyramid reflects a constant tension in the field of conservation: whether to try to return ancient structures to their earlier splendor or minimize intervention as much as possible.